#include <iostream>
#include <string>
#include <vector>

const long long int MOD=1e9+7;
const long long int BASE=31;

using namespace std;

struct RollingHush {
    vector<long long int> hash;
    vector<long long int> power;
    string str;
    
    RollingHush(string s) : hash(s.size()+1), power(s.size()+1) {
        str=s;
        hash[0]=0;
        power[0]=1;
        for(int si=0; si<s.size(); si++) {
            long long int s2lli=s[si];
            s2lli %= BASE;
            
            hash[si+1] = (hash[si]*BASE+s2lli)%MOD;
            power[si+1] = power[si]*BASE%MOD;
        }
    }
    
    long long int get(int left, int right) {
        return ((hash[right]-hash[left]*power[right-left])%MOD+MOD)%MOD;
    }

    int size() {
        return str.size();
    }
};

long long int count_kaibunkai(RollingHush rh, int left, int right) {
    long long int count=1;
    if(right-left<=1) {
        return 1;
    }
    int mid=(left+right)/2;
    while(left<mid) {
        if(rh.get(left, mid)==rh.get(right+left-mid, right)) {
            count += count_kaibunkai(rh, mid, right+left-mid);
        }
        mid--;
    }
    return count;
}

int main() {
    string str;
    cin >> str;
    
    RollingHush rh_str(str);
    
    cout << count_kaibunkai(rh_str, 0, str.size()) << endl;

    return 0;
    
}